Display thumbnail of video

Question

I need to display thumbnail of each video in list view using Picasso library for running faster so i need get thumbnail path to use.

This is my code to get thumbnail path(I found it on Google and i change something to adapt for my application):

String getThumbnailPathForLocalFile(Uri uri)
     {
         Cursor thumbCursor = null;
         try
         {
             thumbCursor = c.getContentResolver().
                     query(uri
                     , null
                     , null , null, null);

             if(thumbCursor.moveToFirst())
             {
                 // the path is stored in the DATA column
                 int dataIndex = thumbCursor.getColumnIndexOrThrow( MediaStore.MediaColumns.DATA );
                 String thumbnailPath = thumbCursor.getString(dataIndex);
                 return thumbnailPath;
             }
         }
         finally
         {
             if(thumbCursor != null)
             {
                 thumbCursor.close();
             }
         }

         return null;
     }

My getView function:

@Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View v = convertView;
        if (v == null) {
            LayoutInflater vi = (LayoutInflater) c
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            v = vi.inflate(R.layout.listview_item, null);
        }

        /* create a new view of my layout and inflate it in the row */
        // convertView = ( RelativeLayout ) inflater.inflate( resource, null );

        final Item item = items.get(position);
        if (item != null) {
            TextView t1 = (TextView) v.findViewById(R.id.txt_fileName);
            imageCity = (ImageView) v.findViewById(R.id.img_icon);

            switch (item.getType()) {
            case "video":
                String uri2 = item.getPath();
                Uri videoUri = MediaStore.Video.Thumbnails
                        .getContentUri(uri2);
                String VideoThumbnailPath =getThumbnailPathForLocalFile(videoUri);
                Picasso.with(c).load(new File(VideoThumbnailPath))
                        .resize(64, 64).into(imageCity);
                break;
            case "image":
                String uri4 = item.getPath();
                Picasso.with(c).load(new File(uri4)).resize(64, 64).into(imageCity);
                break;
            default:
                break;
            }


            if (t1 != null)
                t1.setText(item.getName());

        }
        return v;
    }

I check logcat and debug so i found that thumbCursor is null:

12-10 17:52:38.400: E/AndroidRuntime(8659): java.lang.NullPointerException: Attempt to invoke interface method 'boolean android.database.Cursor.moveToFirst()' on a null object reference
12-10 17:52:38.400: E/AndroidRuntime(8659):     at com.example.knock.FileArrayAdapter.getThumbnailPathForLocalFile(FileArrayAdapter.java:105)
12-10 17:52:38.400: E/AndroidRuntime(8659):     at com.example.knock.FileArrayAdapter.getView(FileArrayAdapter.java:73)

Anybody can help me ? Thanks you very much

Answer 1

Your Uri is not correct. getContentUri(String volumeName) expects the magic word "external" instead of a path. And you may not have a thumbnail yet.

You can load thumbnails with this piece of code

private static final String SELECTION = MediaColumns.DATA + "=?";
private static final String[] PROJECTION = { BaseColumns._ID };
public static Bitmap loadVideoThumbnail(String videoFilePath, ContentResolver cr) {
    Bitmap result = null;
    Uri uri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
    String[] selectionArgs = { videoFilePath };
    Cursor cursor = cr.query(uri, PROJECTION, SELECTION, selectionArgs, null);
    if (cursor.moveToFirst()) {
        // it's the only & first thing in projection, so it is 0
        long videoId = cursor.getLong(0);
        result = MediaStore.Video.Thumbnails.getThumbnail(cr, videoId,
                Thumbnails.MICRO_KIND, null);
    }
    cursor.close();
    return result;
}

What it does is:

1. Look up the video Id of a file by querying Video.Media
2. pass that videoId to getThumbnail which blocks (in your case the ui thread..) until the thumbnail was made & decoded.

Big downside is that you can't use a path for Picasso here. (Custom loading works, https://github.com/square/picasso/blob/master/picasso/src/main/java/com/squareup/picasso/MediaStoreRequestHandler.java seems to be an implementation, some description about it here: http://blog.jpardogo.com/requesthandler-api-for-picasso-library/ )

You can get thumbnail paths, but if you have a look at the content of the thumbnails table, e.g. via this snippet of code

    StringBuilder sb = new StringBuilder();
    Cursor query = getContentResolver().query(
            Video.Thumbnails.EXTERNAL_CONTENT_URI, null, null, null, null);
    DatabaseUtils.dumpCursor(query, sb);
    query.close();
    Log.d("XXX", sb.toString());

You'll see that not every video has a thumbnail.

But those that have can be found via

public static String loadVideoThumbnailPath(String videoFilePath,
        ContentResolver cr) {
    String result = null;
    Uri uri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
    String[] selectionArgs = { videoFilePath };
    Cursor cursor = cr.query(uri, PROJECTION, SELECTION, selectionArgs,
            null);
    long videoId = -1;
    if (cursor.moveToFirst()) {
        videoId = cursor.getLong(0);
    }
    cursor.close();
    if (videoId > 0) {
        Uri uri2 = MediaStore.Video.Thumbnails.EXTERNAL_CONTENT_URI;
        String[] projection2 = { MediaStore.Video.Thumbnails.DATA };
        String selection2 = MediaStore.Video.Thumbnails.VIDEO_ID + "=?";
        String[] selectionArgs2 = { String.valueOf(videoId) };
        Cursor cursor2 = cr.query(uri2, projection2, selection2, selectionArgs2, null);
        if (cursor2.moveToFirst()) {
            result = cursor2.getString(0);
        }
        cursor2.close();
    }
    return result;
}

(still the same PROJECTION & SELECTION constants from above)

Answer 2

One of the way to getting thumbnail of video file is using MediaMetadataRetriever. But this class get frame of video file. So, the size of thumbnail might too bigger than usually thumbnails. Then you may scale that bitmap.

MediaMetadataRetriever mmr = new MediaMetadataRetriever();
Uri url = Uri.parse("android.resource://" + getPackageName() + "/" + R.raw.test); //Your file uri
mmr.setDataSource(getContext(), url);
Bitmap bitmap = mmr.getFrameAtTime();
ImageView imageview = findViewById(R.id.yourimageviewid);
imageview.setImageBitmap(bitmap);

Another way to get thumbnail:

Bitmap bitmap = ThumbnailUtils.createVideoThumbnail(filePath,
MediaStore.Images.Thumbnails.MINI_KIND);